MEP CA AB 1103

Net Zero Energy Buildings - Truth or Fiction?

MEP Energy Star CertificationrA perpetual motion machine has been dreamt of by physicists and engineers alike for centuries and though the possibility of such a thing remains questionable we are growing closer toward a proprietary equivalent (though maybe not in the way you imagine). The Zero Energy Building is on the rise in cities across the globe. These buildings have a net energy footprint of zero, in some cases even less. How is this possible? By utilizing renewable energy technologies and energy efficient practices buildings can simultaneously reduce their energy use while generating energy on-site. The result is a net neutral energy footprint and it is even possible to generate more energy than you end up using. This means instead of being a burden on your community's common resources you become a fount for them.

One major problem the Zero Energy Building movement has faced is the disparity between its proponents(and critics) conceptions of what it entails. Without a clear-cut definition the road to making Zero Energy Buildings the norm is fraught with hurdles. In other words we need to know collectively what we are working towards in order to achieve it. Thankfully this October the US Department of Energy recently released a common definition for the concept. According to the recently released statement a Zero Energy Building is "an energy-efficient building where, on a source-energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy.

Typical on-site renewable energy used to offset a Zero Energy Building's delivered energy include methods like solar water heating, photovaltaics, geothermal energy, wind powered turbines, and more. Some energy sources are more viable depending on climate and available means. For example photovaltaics may not be the most viable option for a building in cloudy Seattle. Architecture can also selectively be used to impact a building's energy efficiency. Variables like shape and orientation can have surprisingly drastic impacts on a structure's energy footprint. One situation in which this becomes apparent is for buildings in cold climates. South-facing structures with large windows can generate as much as 50% of their heat taking advantage of passive solar gain. The necessity of electrical lighting can be mitigated using similar principles of orientation and design.

One of the most important points for a Zero Energy Building is a cradle-to-grave approach. The job is not done once the building is up. System maintenance and life cycle analysis are crucial aspects of the Zero Energy Building. Without regular upkeep and evaluation of energy sources a building can slip back toward being a typical energy consumer. Occupant habits also play a key role in keeping a Zero Energy Building at zero. Conservation allows the renewable energy sources to keep pace with the tenants needs and the less you use the more excess energy is generated. You're already saving utility costs by using these renewable sources, but now that you have an excess of energy generated on site you can make gains by selling it back to the grid.

It is easy to take the energy we use for granted given that all it takes to turn on the lights or control the temperature is an absent minded flick of a switch. Compound this convenience with the fact that residential and commercial buildings account for nearly 40% of the nation's energy use and you have a real problem. There is hope though. The New Buildings Institute and the Zero Energy Commercial Building Consortium recently released a study that claimed there are currently 21 commercial buildings in the US that meet or exceed Net-Zero Energy standards. As technology becomes more available, knowledge and will become more pervasive, and the means become more attainable perhaps the non-Zero Energy building will become a thing of the past. Through engineering and innovation we can cast off the restraints of municipal power and perhaps one day we will find ourselves living in a world where every single residence and business contributes to the communal well of energy rather than draw from it.

Contact MEP today for questions about sustainable commercial building engineering design, as well as assistance with your ENERGY STAR, LEED, AB1103 Benchmarking and Energy Audit needs at 310-782-1410.